San Justo Weather in December

NASA POWER reanalysis for the half-degree grid cell around San Justo, 1991-2020; a grid cell is an area average and can differ from a thermometer in town by several degrees

Average highs run from 31°C on December 1 to 34°C on December 31, and lows from 17°C to 20°C. Normal precipitation for the month is 146 mm over about 12 wet days.

December day by day

The normal high and low for each date, in °C.

Normal low
Normal high
Reanalysis extreme high
Reanalysis extreme low

December at a glance

Average high: 32°C
Average low: 18°C
Precipitation: 146 mm
Reanalysis high: 45°CDec 26, 2013
Reanalysis low: 9°CDec 13, 2010
Daylight: 13 h 59 min to 14 h 07 min
Cloud cover: 52%
Humidity: 61%
Dew point: 16°C
Wind: 13.7 km/h

Every day of the month

A wet day has at least 1 mm of precipitation in the reanalysis.

Date	Normal high	Normal low	Reanalysis high	Reanalysis low	Chance wet
Dec 1	31°C	17°C	38°C 2007	11°C 1993	36%
Dec 2	31°C	17°C	39°C 2004	11°C 2018	36%
Dec 3	32°C	17°C	38°C 1998	11°C 2018	35%
Dec 4	32°C	17°C	39°C 1999	11°C 1994	35%
Dec 5	32°C	17°C	39°C 1995	12°C 2000	34%
Dec 6	32°C	17°C	39°C 1995	10°C 1999	34%
Dec 7	32°C	17°C	39°C 2017	10°C 1999	34%
Dec 8	32°C	17°C	41°C 2008	12°C 2018	34%
Dec 9	32°C	18°C	39°C 1994	10°C 2001	34%
Dec 10	32°C	18°C	41°C 1994	14°C 2005	33%
Dec 11	32°C	18°C	40°C 2019	12°C 2005	32%
Dec 12	32°C	18°C	38°C 2016	12°C 2003	33%
Dec 13	32°C	18°C	41°C 2017	9°C 2010	35%
Dec 14	32°C	18°C	38°C 1995	12°C 2010	37%
Dec 15	32°C	18°C	41°C 2004	12°C 2016	37%
Dec 16	32°C	18°C	44°C 2017	10°C 2000	38%
Dec 17	32°C	18°C	40°C 1995	12°C 2003	37%
Dec 18	32°C	18°C	42°C 1995	15°C 2003	37%
Dec 19	33°C	18°C	43°C 1995	13°C 2015	37%
Dec 20	33°C	19°C	44°C 2011	13°C 2005	37%
Dec 21	33°C	19°C	44°C 2011	13°C 1993	38%
Dec 22	33°C	19°C	41°C 2013	12°C 2019	37%
Dec 23	33°C	19°C	40°C 2007	10°C 2014	38%
Dec 24	33°C	19°C	41°C 2013	11°C 2014	38%
Dec 25	33°C	19°C	43°C 2013	12°C 2011	38%
Dec 26	33°C	20°C	45°C 2013	14°C 2004	37%
Dec 27	33°C	20°C	41°C 2013	13°C 2012	36%
Dec 28	33°C	20°C	40°C 2019	14°C 2012	35%
Dec 29	34°C	20°C	41°C 2013	12°C 2003	35%
Dec 30	34°C	20°C	42°C 2013	13°C 1993	35%
Dec 31	34°C	20°C	40°C 1994	14°C 2020	34%

Chance of rain

Chance of a wet day

Sunrise and sunset

Times for 2026, local time (GMT-3).

December 1: sunrise 5:52 AM, sunset 7:51 PM
December 31: sunrise 6:02 AM, sunset 8:09 PM

Every day of December: sun and moon

Other months

Sources

Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.